The mediation role of hope in the relationship of resilience with depression, anxiety, and stress in caregivers of children and adolescents with cancer

This study aimed to determine the mediation role of hope in the relationship of resilience with depression, anxiety, and stress in caregivers of children and adolescents with cancer. This cross-sectional study was conducted on 200 caregivers of children and adolescents with cancer. Adult Hope Scale, Connor-Davidson Resilience Scale, and Depression, Anxiety and Stress (DAS) scales were used for data collection. The mediator and moderator model was tested using the SPSS macro PROCESS (Model 4, and 5). The mediator model (model 4) indicated that DAS significantly correlated with resilience (β = − 0.54, t-value = − 5.01, p < 0.001), and hope (β = − 0.84, t-value = − 3.45, p = 0.0007). Hope mediated the relationship between resilience and DAS among caregivers of children and adolescents with cancer (Effect = − 0.18, SE = 0.06, 95% CI − 0.33 to − 0.06). The mediator and moderator model (model 5) showed that female caregivers had a stronger correlation between resilience and DAS when compared to their male counterparts (β = − 0.56, t-value = − 3.90, p-value = 0.0001); also, hope mediated the relationship between resilience and DAS among caregivers of children and adolescents with cancer (Effect = − 0.20, SE = 0.08, 95% CI − 0.37 to − 0.04). In conclusion, hope was a mediator, and female caregivers were a moderator in the relationship of resilience with depression, anxiety, and stress, and its promotion might be effective among caregivers of children and adolescents with cancer. It seems that resilience, female caregivers, and hope may provide good protection against depression, anxiety, and stress in caregivers of cancer patients.

experience, may positively affect the family members' activities 16 and quality of life 17 .Hope also decreased the caregivers' burden 17 .Hope is negatively correlated with depression 18 .
As mentioned above, caregivers of cancer patients may experience depression, anxiety, and stress, but resilience and hope, as a coping resource, may be effective in reducing depression, anxiety, and stress in these caregivers.The question is whether there is a relationship of resilience with depression, anxiety, and stress (DAS) in caregivers of children and adolescents with cancer.Few studies reported that resilience was associated with depression and anxiety in caregivers of children and adolescents with cancer 19,20 .Moreover, it was shown that higher resilience was associated with lower level of anxiety and depressive symptoms among family caregivers of patients with advanced cancer 21 .
Another question is whether hope plays a mediating role between resilience and DAS in caregivers of children and adolescents with cancer.A study showed that hope was a mediator in the relationship between resilience and positive coping in cancer patients 22 .Another study indicate that resilience is a dynamic and changeable path that improves hope and decreases depressive symptoms in cancer patients 23 .Another study showed that hope was a mediator in the association between resilience and body image distress in cancer patients 24 .The review of the literature showed that the answers to the above-mentioned questions were ambiguous; most of them focus on cancer patients, not on caregivers, and it is necessary to conduct more evidence-based studies on the relationship between resilience and DAS related to the caregivers of children and adolescents with cancer and the mediating role of hope.Moreover, we asked ourselves whether caregivers' gender could moderate the relationship between resilience and DAS.One study reported that parents' gender was not associated with their resilience, anxiety, and depression 25 .On the other hand, another study showed that the parents' gender was a predictor of resilience 26 .To improve the evidence-based practice, we posed the following hypotheses: (1) Caregivers' DAS will be associated with the demographic and clinical characteristics of the caregivers and their children and adolescents with cancer.(2) DAS (depression, anxiety, and stress) will correlate to resilience, hope, caregivers' gender, and the number of hospitalizations of children and adolescents.(3) Caregivers' gender will moderate the relationship between resilience, DAS, and hope (Figs. 1, 2, and 3).( 4) The number of hospitalization of children and adolescents will moderate the relationship between the caregivers' resilience, DAS (Fig. 4), and hope.(5) Hope will mediate the relationship between resilience and DAS among caregivers of children and adolescents with cancer (Fig. 5).( 6) Caregivers' gender will moderate the indirect effect of resilience on DAS through the mediating effect of hope (Fig. 6).

Mean scores of resilience, and hope, and their subscales as well as depression, anxiety, and stress
Table 2 shows the mean scores of Resilience Scale and Adult Hope Scale, and their subscales as well as DAS.The mean scores of Resilience Scale and Adult Hope Scale were 62.62 (SD = 16.93) and 50.61 (SD = 7.74), respectively.It showed that the Adult Hope Scale was in a moderate level.The mean and standard deviation of depression, anxiety, and stress were 13.00 (SD = 9.00), 13.0 (SD = 9.44), and 17.59 (SD = 9.16), respectively; the caregivers reported mild depression, moderate anxiety, and stress.

The association between caregivers' DAS and the demographic and clinical characteristics of caregivers and their children and adolescents with cancer
Table 1 shows no significant difference between the mean score of DAS and caregiver's gender, marital status, and education, and children and adolescent's gender and age group (years).Moreover, no significant difference Table 1.The demographic and clinical characteristics of caregivers and their children and adolescence with cancer and their association with caregivers' DAS (depression, anxiety, and stress).*Significant.a Independent t-test.b ANOVA.c Pearson correlation coefficient.1).
As shown in Table 1, a significant difference was observed between the mean score of depression and the caregiver's marital status, age of mother, children and adolescents' age group, and number of hospitalizations of children and adolescents during the least 6 months.Moreover, a significant difference was found between anxiety and father and mother's education.In addition, a significant difference was observed between the mean score of caregivers' stress and fathers' education (Table 1).Therefore, based on the findings, some part of hypothesis 1 was approved.

The association between DAS (depression, anxiety, and stress) and resilience, hope, caregivers' gender, and the number of hospitalizations of children and adolescents
As Table 3 shows, a negative and significant association was observed between DAS, depression, anxiety and stress, and resilience and hope.Moreover, a positive and significant association was found between resilience and caregivers' gender.Therefore, based on the findings, some part of hypothesis 2 was approved.

Assess the multicollinearity
To assess the multicollinearity, we used variance inflation factor (VIF) values.The VIF above 10.00 shows that the predictors are multicollinear, and they would be strongly correlated.Based on the results of our study, the VIF of DAS with resilience, hope, gender, and the number of hospitalizations of children and adolescents during the last 6 months was 1.42, 1.39, 1.04, and 1.02, respectively.

The moderator effect of the number of hospitalizations of children and adolescents in the relationship between caregivers' resilience, DAS, and hope
As shown in Fig. 4 and based on the SPSS macro PROCESS, model 1, no moderating effect of the number of hospitalizations of children and adolescents during the last 6 months was observed in resilience and DAS (β = − 0.66, t-value = − 0.32, p-value = 0.74).Moreover, no moderating effect of the number of hospitalizations was found in hope and DAS (β = 4.57, t-value = 1.49, p-value = 0.13).In addition, no moderating effect of the number of hospitalization was reported in the relationship between hope and resilience (β = − 0.67, t-value = − 0.34, p-value = 0.73).Therefore, based on the findings, hypothesis 4 was not approved.Thus, the number of hospitalizations of children and adolescents was not added in the next step and as a moderator.

The mediator effect of hope in the relationship between resilience and DAS among caregivers of children and adolescents with cancer
According to Fig. 5 and based on the SPSS macro PROCESS, model 4, and Table 4, the direct effect of resilience significantly correlated with DAS (β = − 0.54, t-value = − 5.01, p-value < 0.001).DAS significantly correlated with hope (β = − 0.84, t-value = − 3.45, p-value = 0.0007).The indirect effect of resilience on DAS by hope was significant (Effect = − 0.18, SE = 0.06, 95% CI − 0.33 to − 0.06).Therefore, hypothesis 5 was approved.

The moderator effect of caregivers' gender in the indirect effect of resilience on DAS through the mediating effect of hope
Based on Fig. 5 and the SPSS macro PROCESS, model 5, and Table 5, the direct effect of resilience significantly correlated with DAS (β = − 0.80, t-value = -2.39,p-value = 0.01).DAS significantly correlated with hope (β = -0.95,t-value = -3.33,p-value = 0.001).The indirect effect of resilience on DAS by hope was significant (Effect = − 0.20, SE = 0.08, 95% CI − 0.37 to − 0.04).This study showed DAS did not significantly correlate with gender among caregivers of children and adolescents with cancer (β = − 16.37, t-value = − 1.01, p-value = 0.31).No interaction was recognized between resilience and gender (R 2 change = 0.004, F = 0.97, p-value = 0.32).However, based on Table 6 and the result of the moderation mediation model and conditional direct effects of resilience on DAS, female caregivers had a stronger correlation between resilience and DAS when compared to their male counterparts (β = − 0.56, t-value = − 3.90, p-value = 0.0001).Therefore, based on the findings, hypothesis 6 was approved.

Discussion
This study demonstrated the mediating effect of hope and the moderating effect of caregivers' gender on the relationship between resilience and DAS among caregivers of children and adolescents with cancer.
The result of our study showed that the mean score of resilience in caregivers of cancer patients was approximately similar to the studies conducted in Iran 26 and China 25 .However, compared to a study in Turkey 33 , the mean score of caregivers' resilience in our study was higher.Researchers reveal that lived experiences of resilience in parents of children with cancer mean "perceived competence, and social support, going through hardships and positive and negative experience of children's disease" 34 .
In our study, caregivers reported mild depression, moderate anxiety, and moderate stress.Approximately, one-third of the parents with retinoblastoma patients reported depression and anxiety 35 .Another study revealed that roughly 10% of the parents of children with cancer had mild to severe depression disorder 9 .
This study indicated that the mean score of the caregivers' hope was in a moderate level.Similarly, another study carried out on parents of retinoblastoma patients indicated that the score of hope was at a moderate level 35 .Caregivers of cancer patients were hopeful that the illness would be cured and that the survival span would be prolonged 16 .
In our study, the results of the direct analysis effect indicated that resilience negatively correlated with DAS.Similarly, studies reported that resilience was associated with depression and anxiety in caregivers of children and adolescents with cancer 19,20 .An integrative review showed resilience was associated with psychological distress and coping strategies in spousal caregivers of patients with cancer 12 .A higher level of resilience was associated with lower anxiety and depressive symptoms among family caregivers of patients with advanced cancer 21 .
The results of the direct analysis effect on caregivers of children and adolescents with cancer showed that hope positively correlated with the caregivers' DAS.A study indicated that hope had an important effect on anxiety and depression in family caregivers of advanced cancer patients 36 .In fact, hope, as a positive state, reduced depression in cancer patients 18 .
The results of the direct analysis effect of this study indicated that resilience positively correlated with hope in caregivers of children and adolescents with cancer.A study on cancer patients revealed that social support, hope, and resilience predicted the quality of life 37 .
Our study showed that hope mediated the relationship between resilience and DAS.Since no study had been conducted with the same findings as the present study, a comparison was made with other similar studies.Family support, hope, and resilience were associated with depressive symptoms in prostate cancer 38 .A systematic review has shown that the process of resilience begins with the diagnosis of cancer, and it might affect one's mental well-being.Moreover, socio-cultural background and caregivers' characteristics influenced this process 39 .
The result of the moderation mediation model indicated that female caregivers had a stronger correlation between resilience and DAS when compared to their male counterparts and hope mediated the relationship between resilience and DAS among caregivers of children and adolescents with cancer.This is a unique and innovative finding.Another study reported the association between symptom burden and anxiety and depression mediated by resilience in liver cancer patients 40 .

Limitation
This study had some limitations.The type of children and adolescents with cancer that might affect the caregivers was not considered.Therefore, it is recommended that further studies should be conducted on a specific type of cancer.Moreover, this study was conducted on 200 caregivers with cancer; further studies with a larger sample size are suggested to improve the evidence-based practice.

Implication for practice
One of the implications of this study is that the results could be effective for caregivers who take care of children and adolescents with cancer; conducting future research using interventions to increase the levels of hope and resilience is suggested.Since the caregivers' anxiety and stress were at a moderate level, it is useful to provide supportive interventions, including the program to promote resilience and hope for caregivers who take care of www.nature.com/scientificreports/children and adolescents with cancer.Another implication of this study is that it indicated that a portion of the relationship between resilience and DAS in caregivers of children and adolescents with cancer was mediated through hope, while resilience explained a portion of DAS that was independent of hope.This mediated moderator model indicated that the intermediate variable possibly confounded the relationship between resilience and DAS.Moreover, based on our findings, in follow-up studies one can predict DAS from the factors related to well-being, like resilience.Based on our findings, resilience, hope, and the moderator, which was caregivers' gender, explained 24% of the variance in DAS; it means that many well-being factors could be used in these studies.Because the correlation between resilience and hope was high, one could choose any of them.Resilience is a good option, and hope could also be included.

Conclusion
This study showed the direct effect of DAS and resilience with hope in the caregivers of children and adolescents with cancer.Moreover, the relationship between resilience and DAS was significantly mediated by hope in the caregivers of children and adolescents with cancer.In addition, female caregivers had a stronger correlation between resilience and DAS when compared to their male counterparts.It seems that resilient attitudes, female caregivers, and hope might provide a good protection against DAS.

Figure 5. Hypothesised mediation role of hope in relationship of resilince and depression, anxiety, and stress among caregivers of children and adolescents with cancer, based on the "Model 4".
Hypothesised caregivers' gender as moderate in the relationship between resilience,and hope among caregivers of children and adolescents with cancer, based on the "Model 1".

Table 2 .
The mean score of hope, resilience, and their subscales and depression, anxiety, and stress in the caregivers of children with cancer.

Table 3 .
The association between DAS (depression, anxiety, and stress) and resilience, hope, caregivers' gender and the number of hospitalizations of children and adolescents.aDuringthelast6 months.bCorrelation is significant at the 0.01 level (2-tailed).cCorrelation is significant at the 0.05 level (2-tailed).

Table 4 .
The mediate effect of hope in the relationship between resilience and DAS among caregivers of children and adolescents with cancer.

Table 5 .
The moderated mediating effect of resilience on DAS in caregivers of children and adolescents with cancer.Hope as mediator, Caregivers' gender as moderator.a Depression, anxiety and stress.b Standard Error.c Bootstrapping Standard Error.

Table 6 .
Conditional effects of resilience on DAS by caregivers' gender.